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MHT CET2009PhysicsRotational Motion

From a disc of radius R , a concentric dircular portion of radius r is cut out so as to leave an annular disc of mass M . The moment of inertia of this annular disc about the axis perpendicular to its plane and passing through its centre of gravity is

Options

  1. A1 2 M (R²+r² )
  2. B1 2 M (R²-r² )
  3. C1 2 M (R⁴+r⁴ )
  4. D1 2 M^ (R⁴-r⁴ )

Correct answer

A. 1 2 M (R²+r² )

Step-by-step solution

The moment of inertia of this annular disc about the axis perpendicular to its plane will be 1 2 M (R²+r² )

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